Vacuum-pan.



No. 7I|,7l9. Patented Oct. 2|, |902.

M. EKENBERG. f

VACUUM PAN,

(Application led Jan. 8, 1902.)

2 Sheets-Sheet (No Model.)

L4 ATTORNEY Patented Oct. 2|, |902.

VACUUM PAN.

(Application led Jan. 3, 1902.)

2 sheets-sheet z.

(No Model.)

WMM/mono UNITED 'd STATEs.

PATENT V(Driricii.

MARTIN EKENBERG, OF GOTHENBURG, SWEDEN.

VACUUM-PAN.

SPECIFICATION forming part of Letters Patent No. 71 1,719, dated October21, 1902. Application iled January 3, 1902. Serial No..88,290. (Nomodel.)

T0 all whom, it may concern:

Be it known that I, MARTIN EKENBERG, a subject of the King of Sweden andNorway, and a resident of Gothenburg, in the Kingdom of Sweden, haveinvented certain new and useful Improvements in Vacuum-Pans, of whichthe following is a specification.

This invention relates to vacuum apparatus for reducing or condensingliquid substances by evaporation-such as milk, for example; and itbelongs to that class of suoli apparatuses in which a moving part withina vacuum-pan carries up on its surface above the level of the mass ofliquid substance a thin film of the latter, which is thus reduced byevaporation and scraped off. The moving surface may be the surface of arotating drum.

In the present case the novel features of the invention reside partly inthe constructionand arrangement of the drum or moving body inside of thepan, partly in the means for scraping 0E and receiving the condensed orevaporated substance, partly in the means for heating the said drum ormoving body, and partly in other details of the construction.

In the accompanying drawings,which illustrate an embodiment of theinvention, Figure 1 is a vertical mid-section of the apparatus -in itspreferred form, the plane of the section being transversely of the axisof the inner rotatable drum; and Fig. 2 is alsol a vertical section ofthe same, but taken along the axis of the said inner drum. Fig. 3 is aside elevation of the apparatus, and Fig. 4 an end elevation of same asseen from the right in Fig. 3. Figs. 5 and 6 are detail views of themain scraping device. Fig. 7 is a sectional view illustrating somewhatdiagrammatically a means of heating with gas-jets, and Fig. 8 is afragmentary view showing a supplementary roller for applying thesubstance to be condensed to the surface of the moving body or drum. y v

The vacuum-pan 2 is herein shown as provided with an outlet 9, leadingto a powerful exhausting apparatus of the usual kind, (not shown,) apocket 10 to catch the drip, a pipe 11 vto lead the drip back into thepan, a jacket 6 at the bottom to receive steam or other heating medium,and a feeding-inlet 25. Within the pan 2 is a rotatable drum 1, which ishollow, the heads or ends of the drum each having in it a large centralaperture, which may be, however, closed by a cover 3l, Fig. 2, that doesnot rotate with the drum. The annular part 28 of the drum head or endshould or may be wide enough to prevent the liquid substance in thebottom of the pan 2 from overflowing into the drum at its ends, as thecovers 3l, if employed, will not be fixed to the drum.

The drum 1 is driven by a wheel or roller 4, the shaft 4 of whichextends out through the central apertures in the ends of the drum androtates in packed bearings in the sides of the-pan 2. Y On the outer endof the shaft 4 is a driving-pulley 4b, Figs. 3 and 4. As seen in Figl l,the wheel or roller 4 bears on the inn'er face of the hollow drum anddrives itto the right as the parts are seen in Fig. 1. AA bearing andguide roller 4c bears on the inside of the drum at the bottom and tendsto keep the drum down in place. The stationary shaft on which thisroller turns is bent so as to pass out through the central apertures inthe ends of the drum, and it is secured at its extremities in the sidewalls of the pan 2.

Inside of the drum 4 isa fixed hollow heater 3, supplied with steamthrough suitable pipes and passages S. This heater is of a substantiallysemicircular form exteriorly, its curved outer face conformingsubstantiallyto the curvature of the inner face of the drum. Mountedrotatively in the outer face of the heater 3 are rollers 7, which bearupon the drum and form antifriction guides. The pipes 8 and shaft 4awill pass through the non-rotating covers 31, if such covers areemployed, and the pipes pass out through packed apertures in the sidewalls of the pan 2. It will be noted that the several rollers 4, 4, and7form internal guide-bearings to keep the drum in its proper position asit rotates and that the lower side of the drum extends nearly to thebottom of the pan 2.

Preferably there will be a hollow concave heater 3 exterior to the drum1 (see Fig. 1) and adapted to receive steam through a pipe 3b.

At the back of the drum 1 (seen at the left in Fig. l) is a scraper l2,hinged at 15 and held up to an eccentricv 14 by a spring 16. Normallythis scraper is not quite in contact with the drum-surface; but theeccentric enlOO ables it to be set up toward the drum. YAt the front(seen at the right in.Fig..1).is. another scraper, which consists of twocomb-like blades 17' and 18, Figs. 5 and 6, secured on anarm 13, hingedat 15 and furnished with an adjusting-eccentric 20 and compressionspring19. The detail views show the construction plainly, Fig. 5 being a sideView, and Fig. 6 a plan View, of the two scrapingblades. In Fig. 6 itwill be noted that the teeth of the two scrapers are so set that thoseof the scraper 1S come opposite the spaces between those of the scraper17. The arbors of the two eccentrics 14 and 2O extend out through thesides of the pan and are provided exterior to the pan with pointers 30,respec tively, which traverse graduations on the pan. These devices aidin securing accurate adjustment to the Scrapers.

21 is a receiver or chamber to receive the f substance removed by theScrapers 17 and 1S. This substance falls first into a trunk 21a, whichleads it down to the receiver 21. 22 is a hinged valve in the trunkabove Athe re-` ceiver 2l, and 23 is a screw for operating said Valve toopen or cut off communication fbe tween the vreceiver 21 and the pan 2.Thisv valve is to be closed when the Abottom 24' of the receiver 2l isopened for the removal ,1 yof the condensed material or'substancecollected. The valve 22 and hinged bottom 24E` form a kind of air-lockof the receiver 21.

A partition 26 in the bottom of the pan 2 and between the drum 1 andinlet 25 extends above Lthe level of the liquid substance in they panand acts as a baffle or check toprevent'l rotates, as stated, to theright, as seen inl,

Fig. 1, and the milk or other liquid to be condensed is fed in at theinletv 25 in a continuous manner by preference. A vacuum or;

`partial vacuum is maintained in the pan by Only a small part of the rofAsv known means. tating drum is immersed in the liquid. lthe thickenedand partially-condensed liquid f is carried up on the drum the scraper12 removes any surplus, leaving only a thin layer or film on the drum.This layer is condensed, and when it reaches the scraper-blades 17 and18 these scrape it off and it falls down into the receiver 21. The valve22 may be left open normally and be closed only when the cham ber 2l isto be emptied. The operation may be observed through a glazedsight-aperture33 in the trunk, and the interior may be illuminated L bya lamp 27, set in the casing of the pan.

lent may be heated interiorly by means ofiy gas-jets or the like. endsof the drum 1a are left wholly open, and a rentering portion 2LL of thepan 2 extends; into the drum at one of its open ends. Al

In this construction the l gas-pipe 5 extends into the chamber thusformed and has burners for heating the wall of the chamber and throughit the drum.

In Fig. 8 a moditication is shown somewhat diagramatically wherein thedrum 1 does not itselfv extend down into the liquid, but an immersedroller 29 carries the liquid to the lower surface of the drum.

I do not limit myself to the specific construction of the apparatushereinlshown and described, as this may be varied in many respectswithout departing in any material degree from my invention. For example,I have shown several ways of heating the drum or moving `part in thepan; but obviously other means of heating may be employedy as well. AlsoI have shown said moving Apart in the form of` a drum; but it-may haveother forms, and by vthe word.drumfas Vherein used I mean yto imply anyendlessmovable carrying-device having-a surface-which-will take up a lmof the liquid substance, said device operating in combination with meansfor yscraping or removin-g the film ofY condensed substance-from'saidsurface.

`One of `the important lfeatures of my Amachine or apparatus-:is theopen drum, whereby the pressure inside isthe :same las `that outside.The covers 31, if used, doinot close the drum vhermetically.

Having thus described my invention, I claim- 1. In an apparatus for thepurpose specified, the combination wi-thfa vacuum-pan to contain theliquid tobe condensed, a rotating drum in said pan open to theinteriorof the pan so asto equalize thepressure on its outerand inner-faces, aconveX-facediheater within the drum and having its convex face adjacentto the inner face-ofthe drum,fmeans f or supplying a fluid heatingymedium tosaid heater, and means for scraping lthe film of condensedsubstance lfrom said drum.

2. 1In an apparatus for the :purpose speciiied, the combination with avacuum-panto contain the liquid to be condensed, a drum `rotativelymounted insaid .pan and lhearing-a central opening in each end, adriving-wheel within and vbearing on the drum, the shaft of said wheelextending out of theopen ends of the drum and having bearings inthe`pancasing, and means for heating the drum.

3. In an apparatusfor lthe purpose specified, the combination with thevacuum-pan, the rotating drum within `the pan,fand means for scrapingthe condensed substance from the drum, of a steam-heater adjacent ltothe drum, and bearing-rollers between said drum and heater. n

4. In an apparatusfor the purpose specied, the combination with thevacuum-pan, Fig. 7 shows how the drum or its equivaof the open-endedrotating drum within the pan, means for holding the lower side of saiddrum immersed in the liquid, a rotating driving-wheel in the drum andbearing on the inner face of the drum, a scraper in the pan exterior tothe drum and opposite to said driv- IOO IIO

ing-wheel, and means for heating said drum with a iiuid medium.

5. In an apparatus for the purpose specified, the combination with thevacuum-pan,

of the free, open-ended drum within thepan. and rotatable in the liquidtherein, the drivl fied, the combination with the vacuum-pan and therotating drum therein, of the scraper comprising the two comb-likeblades 17 and 18, adapted to bear on the drum obliquely, one in advanceof the other.

7. In an apparatus for the purpose specified, the combination with thevacuum-pan, of the open-ended drum 1 within the same, driving meanswithin the drum for rotating it, a convex, hollow heater Within thedrum, said heater having rollers bearing on the inner surface of thedrum, and two scraper devices, one of said scraper devices being incontact with the surface of the drum and the other .out of contacttherewith, the heater being situated between said scraper devices.

S. An apparatus for the purpose specified comprising a Vacuum-pan, adrum therein having equal pressure on its inner and outer surfaces,means for moving said/drum, interior and exterior heaters which fit upclosely to said dru'm, said heaters being inside of the pan, and meansfor scraping the condensed '35 substance from the outer surface of thedrum.

9. In an apparatus for the purpose speci.- fied, the combination with avacuum-pan, and a drum rotative within said pan, said drum havingcentral openings in its respective ends 4o of less diameter than thedrum, of means for rotating said drum, Vsaid means being situated insideof the drum, a convex-surfaced heater Within the drum, pipes forsupplying a heating inid to said heater through the open 4.5

end of the drum, and Scrapers for removing the condensed substance fromthe drum.

10. An apparatus for the purpose specified, having a vacuum-pan, arotary,horizontal,

open-ended drum within said casing, and a 5o heater within said drum,the surface of said heater conforming in shape to the inner surface ofsaid drum.

In witness whereof I have hereunto signed my name in the presence of twosubscribing 55 witnesses.

MARTIN EKENBERG. \Vitnesses:

ERNST SvANQvIsT, A. F. LUNDBORG.

